I say “partially” self-balancing because it only balances along one axis (forward/backward), and the rider still needs to balance left and right (it’s analagous to riding a bicycle “no hands”). It operates much like a Segway — you lean forward to accelerate, and lean back to brake. The top speed is about 15 mph, and it easily goes 5 miles on a single charge. This is my primary mode of transportation on the MIT campus.